Caltopo is only as accurate as the topographic data that it is based on. 10 METER grid data is common. Think about how terrain can change in 10 meters especially if it is out of date survey. threading the needle using that map data is dangerous. Silverton avalanche from last year is a good example of that.
Let's talk about avalanches, hazards and snowbiking
- Thread starter tribalbc
- Start date
I agree, Cal Too is not accurate enough to solely plan a route with. I do think it is a great tool for looking at unfamiliar terrain.
As for trees anchoring a slope, I use the rule that "if the trees are spaced apart enough to ski then the slope can still slide".
Thanks again for the great discussion.
Clicked that link, surprised they sell them for $25! Even more impressed, the 2 day awareness course I took here in Gallatin gave them away to everyone who showed up and it has been in my jacket since. Super useful tool any time I think a slope might even remotely be sketchy steepness and it really helped me to calibrate my internal measurement of what a safe angle is on sight.
Far too many deaths in the past two weeks. One snowmobiler yesterday in Washington. Please be safe. Even "experts" are getting caught in slides. Persistent slabs under lots of new snow is an extremely dangerous condition.
Feb 6 Saturday morning in Western Montana, we go to breakfast at 7 and discuss the weekend riding.
1. Its snowing like crazy out side ?
2. Not a tough decision to make, Stay HOME!!!!
Feb 7. 7 am phone conference, windblowing like crazy, new fluffy snow building and making windloaded East facing slopes, temp dropoping........easy lookout the window decision...........StayHome.
45 years of motorized snow recreatrion you learn a few things, a look out the window ?
Big weekend for avalanche deaths, one closeby here in Montana, nothing but sympathy for their families, so sad.
1. Its snowing like crazy out side ?
2. Not a tough decision to make, Stay HOME!!!!
Feb 7. 7 am phone conference, windblowing like crazy, new fluffy snow building and making windloaded East facing slopes, temp dropoping........easy lookout the window decision...........StayHome.
45 years of motorized snow recreatrion you learn a few things, a look out the window ?
Big weekend for avalanche deaths, one closeby here in Montana, nothing but sympathy for their families, so sad.
VIDEO: Snowmobiler Captures Terrifying Moment Huge Avalanche Engulfs and Buries His Group in Utah - SnowBrains
A video caught by a backcountry snowmobiler captures the moment a huge avalanche in the Utah backcountry barreled down on him and his group
It was a snowbiker, with a deployed airbag. Buried 4 feet down, near his partner who was only partially buried. The partner self extracted, attempted a search, then went out to get help. The full report isn't out, but NWAC did put out a quick 1 minute video with a run down.
The core of my riding group did an avalanche rescue course with Mike Duffy 3 weeks ago about 1.5 air miles from where that avalanche happened.
You can not play around with a buried Persistent Weak Layer (i.e. faceted grains or surface hoar). These types of weak layers can "persist" and cause avalanches time and time again over a long duration. They are unpredictable. Your only sane choice when dealing with these buried weak layers is to stay off of and out from underneath slopes that are 30˚ or steeper. This stuff will bite you long after you think there's nothing going on. This is the case this year here in Utah and things will continue to be dangerous for some time to come.
Your best and easiest defense is to learn how to judge slope angles. To do this, go out and start guessing what the steepness of various slopes are and then measure the slopes. I use an app called Theodilite but there are many out there. Choose one where you can sight down or up the slope as well as hold the phone sideways on a hill for a reading. Do this regularly and eventually you will start getting pretty good at estimating. Most importantly, you'll be able to recognize slopes that are steep enough to avalanche.
You don't have to stay home when it's puking out and the avalanche danger is high. You just need to avoid steep slopes.
You don't have to stay home when it's puking out and the avalanche danger is high. You just need to avoid steep slopes.
Is it Theodolite? vs Theodilite?, cant find the latter?
M5
M5
Your best and easiest defense is to learn how to judge slope angles. To do this, go out and start guessing what the steepness of various slopes are and then measure the slopes. I use an app called Theodilite but there are many out there. Choose one where you can sight down or up the slope as well as hold the phone sideways on a hill for a reading. Do this regularly and eventually you will start getting pretty good at estimating. Most importVIDEO: Snowmobiler Captures Terrifying Moment Huge Avalanche Engulfs and Buries His Group in Utah - SnowBrains
A video caught by a backcountry snowmobiler captures the moment a huge avalanche in the Utah backcountry barreled down on him and his groupsnowbrains.com
Looks like we need to talk about remote triggering and overhead hazard.
Things have been mellow here in coastal BC but we are going through a week of artic outflows. Next big snowfall will likely get electric.
N
n16ht5
Well-known member
I came from BC skiing background, and found my approach to avy danger a bit different than a lot in the moto community. The idea that just staying home on "high risk" days and then hitting exposed terrain on other days seems to run strong in the moto community. I usually ride with the expectation that anything that can slide will, unless it just did. So I try to minimize my risk and line choices. Being that I do ride in the steep terrain I know I am usually taking a risk when I ride in general. Below... I was riding on top of a spine and dipped a hair below the top in dense trees. The terrain quickly got vertical with a short open section. I stopped to take a look and found I was at the very top of the opening, so I made a quick ski cut across, and it slid below me. About a 2ft crown, a good ways into very steep dense trees below. Had I been a few yards lower I would not have cut across, as I would have been on a bad ride. A lot of times skiing in backcountry we would be hitting steep chutes. We tested them with ski cuts, sometimes setting them off.
Well this was a new one for me. Dumping here in Utah!
Pretty full on.
Time to ride flat trees far from any avalanche terrain.
Good thing with snowbikes is that's still fun.
We have had more than a week of cold and snow event, nothing major, but Sat morning we will find " blower powder " and worse the higher you go. The snow out here right now in our riding area will be accompanied by poor flat light, periods of " white out " and snow your 174 blower skidoo will not go through on flat ground. So besides the obvious avalanche danger, these conditons produce the rescue missions ( two so far this week ) where 10 guys risk their own lives to try and find the pilgrims that dropped into that draw, disoriented, mid afternoon, should have kept the tailights on the pickup in sight all day.
So.........don't be stupid, nice days will come along, the snow will settle, avalanche danger may be extreme for another month if not the rest of the year, nothing wrong with going back home for lunch at 11. This ain't the superbowl.
So.........don't be stupid, nice days will come along, the snow will settle, avalanche danger may be extreme for another month if not the rest of the year, nothing wrong with going back home for lunch at 11. This ain't the superbowl.
Here’s today. Wild.
Thank you to all the experts helping out it, it's great to have access to this info!
How does past traffic factor in to evaluating a slope? A lot of hill climbs we all play on see traffic all year and I would think that slide potential is greatly reduced when a hill is tracked up but is that always the case?
How does past traffic factor in to evaluating a slope? A lot of hill climbs we all play on see traffic all year and I would think that slide potential is greatly reduced when a hill is tracked up but is that always the case?
Compaction definitely helps but it isn't a simple answer.
It really depends on the avalanche problem.
If the entire slope that you climb gets completely compacted regularly then you could certainly feel better about it than a similar non compacted slope. But even that compacted slope with very warm temps in the spring and an isothermic snowpack your benefits are gone again.
"it depends" is often the answer. It is the thin spots that usually are the trigger. Or the wind loaded spots that look great but are ready to pop.
I read incident reports all the time about spots that were ridden the days before without issue and slide the next day. Some like in Utah they put 15 tracks on it before it killed 4 people.
I read incident reports all the time about spots that were ridden the days before without issue and slide the next day. Some like in Utah they put 15 tracks on it before it killed 4 people.
